We've been asked this so many times now, it's practically become a parody of itself. We know what the questioner really wants to hear. We're just waiting for her to drop the 'Jesus bomb'. And so we tire of it. That's why the phrase, "reason for the season", can't be uttered without cringing. It's become trite and self-obvious.
To ask about the meaning of Christmas too often means entertaining this reality. However, it's sometimes suggested that the question can be short-circuited entirely, arguing that Christmas actually has a rather messy history, much of it pagan in design. We're informed that Christmas trees owe their existence to several pre-Christian teutonic customs. It's suggested that Santa Claus is primarily a commercial construction, perhaps with links to Odin, a Norse God. And, as the piece de resistance, the very existence of Christmas as a Christian celebration is said to have derived from Sol Invictus, a pagan celebration of the sun, set during the winter solstice.
As for me, I'm not that convinced. Not because I'm desperate to crowbar Christianity into every December conversation. Because I'm not. But nor - more importantly - do I think The Nazarene can be avoided this easily.